Avatar Compressor (Synthos Edition)

A non-destructive avatar texture optimization utility for VRChat. Create lightweight avatars that drastically reduce VRAM usage and download size so more players can see you.

This repository is a customized edition of Limitex’s Avatar Compressor (LAC) (under the MIT License), tailored to run completely independent of NDMF (Non-Destructive Modular Framework) with native VRCFury and standard VRCSDK build pipeline support.

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What Was Changed?

1. NDMF Dependency Completely Removed

   • In Stock Avatar Compressor: You could only use it through NDMF (nadena.dev.ndmf), requiring extra third-party frameworks and forcing avatars through the NDMF build lifecycle.
   • In Synthos Edition: NDMF is completely stripped. It runs natively using VRChat’s official avatar build pipeline callbacks (IVRCSDKPreprocessAvatarCallback).

2. Native VRCFury Integration

   • Implements AvatarCompressorVrcfuryBuildHook running at callbackOrder => 10000.
   • VRCFury executes at callbackOrder => -10000, so all modular clothing, toggles, props, and merged animators are already assembled before Avatar Compressor analyzes and compresses textures.

3. Direct Animator & Controller Scanning

   • Replaced NDMF’s internal AnimatorServicesContext with direct avatar hierarchy and VRCAvatarDescriptor controller scanning.
   • Collects all animation clips (including FX, Gesture, Action layers and sub-state machines) to protect animated textures and update object curves to point to compressed textures and cloned materials.

4. Self-Contained Localization & UI

   • Bundled translations (English, Japanese, Korean, Simplified Chinese, Traditional Chinese) are parsed directly from PO files without requiring NDMF’s localization system.
   • Works immediately in any Unity Editor project.

5. Manual Editor Compression Tool

   • Added Tools > Avatar Compressor > Compress Selected Avatar to allow creators to preview and test compression in the Editor without needing a full VRChat upload.

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What Is No Longer Needed?

• NDMF (nadena.dev.ndmf) is NO LONGER required: You do not need NDMF installed in your project.
• Works seamlessly with VRCFury and standard VRCSDK3.

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Features

Texture Compressor

Analyzes and compresses avatar textures based on their complexity:

• Complexity-based analysis - Textures are analyzed to determine optimal compression levels.
• Multiple analysis strategies - Fast, HighAccuracy, Perceptual, and Combined modes.
• Preset configurations - Quick setup with 5 built-in presets (High Quality, Quality, Balanced, Aggressive, Maximum, Custom).
• Texture type awareness - Specialized handling for normal maps, emission maps, and alpha masks.
• lilToon integration - Optional baking of color adjustments, alpha masks, and pruning of unused texture slots.
• Platform-specific formats - Automatic format selection for PC (DXT/BC) and Quest (ASTC).
• GPU Accelerated - Uses GPU compute shaders for ultra-fast texture analysis and area-averaging resize with automatic CPU fallback.
• VRAM estimation - Inspect and preview estimated VRAM usage directly in the inspector.

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Requirements

• Unity 2022.3 (VRChat specified version)
• VRChat SDK Avatars 3.10.0 or later
• (Optional) VRCFury

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Installation via VPM (VRChat Creator Companion / ALCOM)

Add the Synthos package repository to VCC / ALCOM:

https://grimreaper35487.github.io/Synthos-VRC-Packages/index.json

Then add Avatar Compressor (Synthos Edition) to your project.

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Usage

1. Add the TextureCompressor component to your avatar’s root GameObject.
2. Select your desired compression preset (e.g. Balanced or Quality).
3. Test or upload your avatar:
   • Automatic: When uploading via the VRChat SDK (or testing in Play Mode with VRCFury), textures are automatically compressed and applied during the pre-upload process without modifying your original project files.
   • Manual: Use Tools > Avatar Compressor > Compress Selected Avatar from the top menu bar to test on an avatar instance in your scene.

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License

MIT License

Original Author

• Original LAC tool by Limitex
• Decoupled and modified for VRCFury by Synthos